A preposition shows the relationship between a noun or pronoun and another word in the sentence. English prepositions often indicate time, place, direction, or manner. The noun or pronoun after a preposition is called the object of the preposition. Common prepositions appear before nouns, pronouns, or noun phrases. The meaning of a preposition depends on context.

In is used for enclosed spaces, larger areas, and time periods such as months, years, and parts of the day. In often suggests being inside a place or within boundaries. In can also indicate being within a group or category. In can mark duration when combined with time expressions. In is not typically used for specific days or clock times.

Word/Phrase	Definition
in	In shows being inside a space or area
in	In marks months and years as time periods
in	In marks parts of the day except night

On is used for surfaces and for public transport. On marks specific days and dates. On can indicate attachment or contact with a surface. On can also refer to devices or media. On is not usually used for general months or years.

Word/Phrase	Definition
on	On shows being on a surface
on	On marks specific days and dates
on	On shows being on transport or media

At is used for specific clock times and precise points or locations. At often marks addresses when the number is given. At can indicate events as points in time or place. At can show a particular stage or level. At is not used for broad areas or time periods.

Word/Phrase	Definition
at	At marks exact times
at	At marks precise places or points
at	At marks events as points in time or location

By is used to show means or method, such as travel or communication. By can indicate the agent in passive sentences. By can show proximity, meaning near. By can mark a deadline, meaning before or at a certain time. By is different from with, which usually refers to accompaniment or tools.

Word/Phrase	Definition
by	By shows means or method of doing something
by	By marks the agent in passive voice
by	By marks a deadline or endpoint in time

With is used to show accompaniment. With can indicate the tool or instrument used to do something. With can express manner or the way something is done. With can show possession or features. With is different from by, which focuses on method or agent.

Word/Phrase	Definition
with	With shows being together with someone or something
with	With shows the tool or instrument used
with	With shows manner or characteristics

To is used to show direction or movement toward a place. To marks the indirect object in many verb patterns. To is used before the base form of a verb in the to-infinitive. To can indicate a limit or endpoint. To is not the same as for, which often shows purpose or benefit.

Word/Phrase	Definition
to	To shows movement toward a destination
to	To introduces the to-infinitive form
to	To marks a limit or endpoint in range

For is used to show purpose or reason. For often indicates who receives something or who benefits. For can mark duration, meaning how long something lasts. For can show support or preference. For is different from to, which often shows direction or the infinitive.

Word/Phrase	Definition
for	For shows purpose or reason
for	For shows benefit or recipient
for	For shows duration of time

Of shows possession or belonging. Of is used to describe parts of a whole. Of can indicate a characteristic or quality. Of is common in fixed expressions and noun phrases. Of does not usually indicate location or movement.

Word/Phrase	Definition
of	Of shows possession or relationship
of	Of shows parts of a whole
of	Of shows a characteristic or quality

From shows the starting point of movement or change. From can indicate origin, such as a place or source. From is used with to to show a range. From can mark separation or difference. From is not usually used to show direction toward a place.

Word/Phrase	Definition
from	From shows the starting point of movement or time
from	From shows origin or source
from	From shows separation or difference

Over often means higher than and possibly covering or crossing. Above means higher than but not necessarily covering. Over is common with movement across an area. Above is common with measurements or fixed positions. The choice depends on whether coverage or movement is involved.

Word/Phrase	Definition
over	Over means higher than and may involve coverage or crossing
above	Above means higher than without coverage
over	Over is used with movement across an area

Common English prepositions include in, on, at, by, with, to, for, of, and from. Each preposition has typical contexts for time, place, direction, or manner. Accurate use depends on the relationship you want to express. Many errors come from choosing the wrong preposition for the intended meaning. Consistent practice builds intuition for these patterns.